Recent improvements in electrical data transmission, especially in the computer field, have resulted in the ability to transmit data along transmission lines at increasingly higher data rates. Further, similar improvements have also seen the decrease in the size of the equipment used in the industry. In order to function effectively with such equipment, the interconnection technology, such as the electrical cables and electrical connectors which connect such equipment, has also undergone significant improvements. Electrical connectors are now smaller and capable of transmitting data at higher rates between such components.
The requirement to make the electrical connectors smaller necessitates putting the conductive contacts of such connectors in closer proximity. However, when transmitting data at higher data rates, this physical proximity has a tendency to increase the cross-talk levels between adjacent electrical contacts supported in the connector. Such cross-talk may adversely effect the electrical performance of the connector. Thus, effective internal shielding must be provided as between selected contacts supported within the connector.
Similarly, these electrical connectors may be used in areas which may be subjected to externally induced interferences from other components, radio frequency interference (RFI) and electromagnetic interference (EMI) may also adversely effect connector performance. Accordingly, the industry has also seen the need for improving electrical shielding of the connectors so as to shield such connectors from these external interferences.
The need for effective shielding both internally and externally, is especially seen in connectors used in closed-loop data systems which provide for continuity of signal in a multi-component system when certain of the connectors are not interconnected. These closed-loop systems employ connectors containing devices which permit automatic shunting so that a closed-loop connection is maintained even when a connector is in a non-connected condition. The shunting devices used in these connectors render effective shielding even more problematic.
Further, as shielding is to be provided both internally and externally, ground continuity between the internal and external shielding is desirable. These connectors should provide a continuous ground path between the external and internal shields.
It is, therefore, desirable to provide an electrical connector which provides for continuous shielding in a compact connector design which shields selected contacts supported within the connector as well as shields the connector from outside interferences.